<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
	<script src="js/vue.js"></script>
	<title>Document</title>
	<style>
		.active{text-decoration: underline;}
		.text-danger{font-weight:bold;}
	</style>
	</head>
	<body> 
		<div id="app">
				<div v-bind:class="[activeClass,errorClass]">Hello Vue!</div>
			</div>
		</body>
		<script>
			var vm = new Vue({
				el: '#app',
				data: {
					activeClass:'active',
					errorClass:'text-danger'
				}
			})		
		</script>
	</body>
</html>